The invention relates to hawser line flotation.
Hawser flotation is attached about hawser line used, e.g., on single point moorings (SPM) for off-shore oil ports. Hawser lines, which typically have circumferences of 5 to 30 inches and breaking strengths of over 20,000 kgs. (for a 5-inch circumference line) to over 600,000 kgs. (for a 21-inch circumference line), are provided as hawser units, typically weighing 2,200 kgs. or more per 100 feet for the larger sizes, with hawser floats and terminations in place. The hawser units are installed at the single point mooring and are left in place for the life of the line, typically about 6 to 8 months.
The hawser flotation keeps the line afloat when not in use and provides protection against chafing and abrasion where the line is covered by the floats. The line, of course, stretches when in use due to the extreme weight of the oil tanker, and contracts when the weight is removed. Thus the flotation elements, which have fixed length, are spaced, leaving sections of line therebetween exposed to the elements and to wear. The flotation elements, which are initially installed at the rope works, also must be spaced to permit the hawser to be bent for crating and shipping.
The flotation elements are also subject to damage and loss during use. Periodic hawser inspections are conducted on location, and it is desirable that missing or damaged elements be replaced. However, the process required for lacing the new elements about the hawser is typically time consuming and difficult, and under normal working conditions has not been done except where absolutely required. Thus portions of the hawser line have been left exposed to chafing, wear, and other damage, with a resulting shortening of the useful life of the hawser.
It is the objective of this invention to provide hawser flotation which may be positioned about the hawser in close proximity to adjacent floats to minimize the section of rope exposed to wear.
It is a further objective to provide hawser flotation which is easily installed on the hawser line, either at the rope works or in the field, and also to provide a simple method of installing the new hawser float elements.